A Liquid Crystal Display (LCD) device has a pair of substrates and a liquid crystal layer between the substrates. Voltages are applied to the liquid crystal layer via electrodes formed on the substrates to change the alignment of liquid crystal molecules, thereby changing the polarization of the light passing through the liquid crystal layer so that images are displayed.
The pair of substrates sandwiching the liquid crystal layer have a certain distance (cell gap) therebetween kept by a spacer and are attached to each other by a sealing material. Examples of the spacer include a transparent bead-shaped spacer. Since the contrast may be lowered if the spacer is ununiformly dispersed, a pillar-shaped spacer may also be used (see Patent Literatures 1 to 6, for example).
For simplification of the production process, the pillar-shaped spacer may be produced by the following process. Upon formation of color filters of plural colors such as red, green, and blue in a pixel aperture region, color filters of the same colors are formed at a predetermined plural sites on a black matrix. In this manner, protruded portions formed of stacked color filters of three colors including red, green, and blue are formed, and these protruded portions are used as pillar-shaped spacers (see Patent Literatures 7 to 9, for example).
Commonly, the pair of substrates sandwiching the liquid crystal layer includes an array substrate having an electrode for application of the voltage to the liquid crystal layer, wirings, and a switching element such as a TFT (Thin Film Transistor), and a color filter substrate having a color filter for color display, and a black matrix, as two individual substrates.
Recently, a so-called color filter (CF) on array system is studied in which members such as a color filter and a black matrix are formed on an array substrate. In the CF on array system, margins for position adjustment of the members formed on each of the pair of substrates are not needed, so that the production process can be simplified and the pixel aperture ratio can be increased (see Patent Literature 10, for example).